The art of simultaneously extruding a meat emulsion material into a casing while also extruding a second material such as chili or cheese into the interior of the casing to ultimately form a frankfurter or the like filled with the interior material is an old art. However, efforts to practice this art on modern meat encasing machines, such as that generally shown in U.S. Pat. No. 3,115,668, have not met with the success that is necessary to adapt this process to rapid, mass production requirements.
For example, recent efforts to make this adaption of filling the center of a frankfurter or the like with a condiment is illustrated in U.S. Pat. Nos. 4,569,101 and 4,570,298. However, it is believed that the concept of these patents interferes with the free flow of the material being used and this results in damage to the material being utilized. Also, the devices of these patents and others are complex in construction, less sturdy than is desired for mass production requirements, and more difficult to clean.
In addition, difficulty exists with prior art devices insofar as controlling the coordinated rate of extruding two materials simultaneously into the casing material.
Therefore, it is an object of this invention to provide a compound pump mechanism for meat encasing machines and the like whereby dual pumps are used for the dual extrusion process and wherein the pumping operations of the two pumps can be carefully coordinated and controlled.
A further object of this invention is to provide a compound pump mechanism for meat encasing machines and the like wherein two pumps are provided with a single source of operational power.
A still further object of this invention is to provide a compound pump mechanism, wherein the pumping capacity of one pump can be selectively adjusted with respect to the other pump.
A still further object of this invention is to provide a compound pump mechanism wherein two pumps are powered by the same common drive shaft with the pump capacity of one pump being selectively adjustable with respect to the other pump, and wherein the speed of operation of the common drive shaft will maintain the proportionate pumping capacities of both pumps.
A still further object of this invention is to provide a compound pump mechanism, wherein dual pumps can deliver material being pumped to the ends of concentrically positioned inner and outer stuffing horns without damaging the pumped material.
A still further object of this invention is to provide a compound pump mechanism, wherein the entire apparatus can be easily cleaned and wherein the pumping structure and the means for supplying the pumped material to the ends of the concentrically arranged stuffing horns are simple of manufacture, and structurally sound.
These and other objects will be apparent to those skilled in the art.